/************************************************************************
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 * 
 * Copyright 2008, 2010 Oracle and/or its affiliates. All rights reserved.
 * 
 * Use is subject to license terms.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy
 * of the License at http://www.apache.org/licenses/LICENSE-2.0. You can also
 * obtain a copy of the License at http://odftoolkit.org/docs/license.txt
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * 
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 ************************************************************************/
package org.odftoolkit.odfdom.pkg.rdfa;

import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import javax.xml.namespace.NamespaceContext;

/**
 * EvalContext modified from net.rootdev.javardfa.EvalContext
 */
final class EvalContext implements NamespaceContext {

    EvalContext parent;
    String base;
    String parentSubject;
    String parentObject;
    String language;
    String vocab;
    List<String> forwardProperties;
    List<String> backwardProperties;
    Map<String, String> xmlnsMap = Collections.EMPTY_MAP;
    Map<String, String> prefixMap = Collections.EMPTY_MAP;

    protected EvalContext(String base) {
        super();
        this.base = base;
        this.parentSubject = base;
        this.forwardProperties = new LinkedList<String>();
        this.backwardProperties = new LinkedList<String>();
    }

    public EvalContext(EvalContext toCopy) {
        super();
        this.base = toCopy.base;
        this.parentSubject = toCopy.parentSubject;
        this.parentObject = toCopy.parentObject;
        this.language = toCopy.language;
        this.forwardProperties = new LinkedList<String>(toCopy.forwardProperties);
        this.backwardProperties = new LinkedList<String>(toCopy.backwardProperties);
        this.parent = toCopy;
        this.vocab = toCopy.vocab;
    }

    public void setBase(String abase) {
        // This is very dodgy. We want to check if ps and po have been changed
        // from their typical values (base).
        // Base changing happens very late in the day when we're streaming, and
        // it is very fiddly to handle
        boolean setPS = parentSubject == base;
        boolean setPO = parentObject == base;

        if (abase.contains("#")) {
            this.base = abase.substring(0, abase.indexOf("#"));
        } else {
            this.base = abase;
        }

        if (setPS) this.parentSubject = base;
        if (setPO) this.parentObject = base;
        
        if (parent != null) {
            parent.setBase(base);
        }
    }

    @Override
    public String toString() {
        return
            String.format("[\n\tBase: %s\n\tPS: %s\n\tPO: %s\n\tlang: %s\n\tIncomplete: -> %s <- %s\n]",
                base, parentSubject, parentObject, language,
                forwardProperties.size(), backwardProperties.size()
                );
    }

    /**
     * RDFa 1.1 prefix support
     * @param prefix Prefix
     * @param uri URI
     */
    public void setPrefix(String prefix, String uri) {
        if (uri.length() == 0) {
            uri = base;
        }
        if (prefixMap == Collections.EMPTY_MAP) prefixMap = new HashMap<String, String>();
        prefixMap.put(prefix, uri);
    }

    /**
     * RDFa 1.1 prefix support.
     * @param prefix
     * @return
     */
    public String getURIForPrefix(String prefix) {
        if (prefixMap.containsKey(prefix)) {
            return prefixMap.get(prefix);
        } else if (xmlnsMap.containsKey(prefix)) {
            return xmlnsMap.get(prefix);
        } else if (parent != null) {
            return parent.getURIForPrefix(prefix);
        } else {
            return null;
        }
    }

    // Namespace methods
    public void setNamespaceURI(String prefix, String uri) {
        if (uri.length() == 0) {
            uri = base;
        }
        if (xmlnsMap == Collections.EMPTY_MAP) xmlnsMap = new HashMap<String, String>();
        xmlnsMap.put(prefix, uri);
    }

    public String getNamespaceURI(String prefix) {
        if (xmlnsMap.containsKey(prefix)) {
            return xmlnsMap.get(prefix);
        } else if (parent != null) {
            return parent.getNamespaceURI(prefix);
        } else {
            return null;
        }
    }

    public String getPrefix(String uri) {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    public Iterator getPrefixes(String uri) {
        throw new UnsupportedOperationException("Not supported yet.");
    }
    
    // I'm not sure about this 1.1 term business. Reuse prefix map
    public void setTerm(String term, String uri) {
       setPrefix(term + ":", uri);
    }

    public String getURIForTerm(String term) {
        return getURIForPrefix(term + ":");
    }

    public String getBase() {
        return base;
    }

    public String getVocab() {
        return vocab;
    }
}

/*
 * (c) Copyright 2009 University of Bristol All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer. 2. Redistributions in
 * binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other
 * materials provided with the distribution. 3. The name of the author may not
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

